The invention relates to a device for dispensing either one component or multi-component compounds from at least one cartridge. This device includes a punch that is supported in a displaceable manner which is associated with each cartridge and is used to apply pressure to the cartridge. These devices are used as metering and mixing devices for dispensing a basic component and a catalyst component. These components are mixed with each other to form a compound for producing impressions in the dental field.
The cartridges are formed as hose like pouches that are emptied by the pressure applied by the punches, so that the components discharged into the mixer are blended in this mixer to obtain a compound that is ready to be used for impressions. In addition, this invention relates to a valve arrangement that can be used with this type of a device.
Devices for dispensing compounds are known in the art. For example, European Patent No. EP 492 413 A1 discloses two plungers that can be displaced from cartridges for mixing and dispensing two-component compounds. These plungers are jointly driven by an electric motor via a magnetic clutch and a chain drive. At the same time, this motor is rotationally driving a shaft which is connected to the mixer to intimately blend the components with each other.
In addition, a dispensing device for cartridges is also known from the art. For example, European Patent No. EP 1 101 638 A2 discloses a set of tappet plates that can be displaced with a carriage by means of an electromechanical driving system and threaded spindles. In addition, a device for dispensing a multi-component compound is also disclosed by European Patent No. EP 1 010 401 A1. With this device, the punch acts on cartridges that can be driven by an electric motor via a threaded spindle.
Furthermore, European patent No. EP 787 515 B discloses a dispensing device for dispensing at least two components. This device comprises a metering cylinder with a feeding plunger for each component. This device also includes a drive unit that is actuated either electrically, pneumatically, or by hand for operating this device.
After these devices have been shut off, the drive of the plungers should come to a standstill immediately to prevent the feed of the two components that are to be mixed with each other. Thus, this feeding will not continue, so that the dispensed compound can be exactly metered out and so that it is not contaminated by flowing back into a mixer and thus, these components will not set back in the mixer.
To control this flow, and prevent the setting of these components in the mixer, European Patent No. 492 413 A1 uses a magnetic clutch that can be engaged and disengaged when the motor drive of the plunger is switched on and off. With this design, the plungers are connected with the motor drive via this magnetic clutch. Thus, this structure for applying single- or multi-component compounds is made very complicated and therefore, the manufacture of this type of a device is very expensive. Additionally, many components required for the drive of these plungers are subject to repair. The operating costs of these plungers is high as a consequence of the required maintenance and repair work.
In addition, another drawback with some of the known devices listed above is that it is possible that after the drive has been shut off, one of the components may flow from a first cartridge into a mixer or into a second cartridge, where it will mix with the other compound received there. When the components comprise a basic component and a catalyst component, these components cure in the mixer so that this mixer gets clogged and becomes unstable.
Therefore, the problem of the invention is to provide a device which can exactly meter out components with a high volume output of dispensed material, wherein this device requires a low amount of repair work, and wherein this device can be manufactured with a minimal number of components, in a compact way, and at a favorable cost.
In addition, another problem of the invention is to provide a valve arrangement with a high volume opening that can be opened with low setting forces even at high pressure.